The BBC carries a story on the energy waste represented by household appliances kept on standby mode instead of being switched off. The UK alone wastes enough energy to send the population of Glasgow on a return flight to New York. The problem is that contrary to what most people (including me) believed, keeping an appliance on standby mode doesn’t save that much energy. From the article, some television sets run at about two-thirds consumption when on standby mode, rather than at just a fraction.

We’ve seen a similar problem in our lab. One of our printers, a Xerox Phaser 8200, used to be left on standby over the evenings and the weekends. Out of curiosity we once measured the printer’s consumption when under standby and found about 150 W, about the same amount of energy needed to keep two lightbulbs glowing. Let’s say nobody uses the printer between 6 pm and 8 am (14 hours), and you are left with a daily bill for about 2 kWh wasted. Under very optimistic assumptions, this is about the energy produced by two square meters of solar panels in Lausanne on a sunny day. Or to put it another way, at 11 swiss centimes per kWh during non-peak hours (roughly what we pay at our place in Geneva), it translates to 73 swiss francs per year.

Sure it irritates me to have to wait for warm-up when I send a print job to the printer in the morning. But if it were “my” money, would I pay that amount per year because I cannot wait for five minutes? Or because I cannot bring myself to remember to switch on the printer on when I arrive in the office? (The printer sits precisely on the way to my office.)

Update: I learned from some educational flyers in our institute that Europe requires the equivalent of six nuclear reactors just to keep devices on standby, or even switched off because of the inefficiency of some transformers.